Liquid fuel injection pump for internal-combustion engines



J1me 1953 A. MURASZEW 2,640,420

LIQUID FUEL INJECTION PUMP FOR INTERNAL-COMBUSTION ENGINES Filed June15, 1951 -A HHHH H IHII II! Patented June 2, 1953 LIQUID FUEL INJECTIONPUMP FOR INTERNAL-COMBUSTION ENGINES v Alexander Muraszew, London,England, assignor to C. A. V. Limited, London, England Application June15, 1951, Serial No. 231,807 In Great Britain July 25, 195i) Thisinvention relates to liquid fuel injection pumps for multi-cylinderinternal combustion engines, and has for its object to provide animproved pump of the kind comprising a single plunger reciprocable in acontaining barrel, and a rotary distributor for directing the fueldischarged by the plunger from the barrel to each in turn of the enginecylinders.

The invention comprises a pump of the kind aforesaid, having combinedtherewith a springloaded reciprocatory and rotatable discharge valvewhich (by its reciprocatory motion) controls the outlet from the pumpbarrel, and which (by its rotary motion) serves as the distributor.

In the accompanying drawings:

Figure 1 is a sectional side elevation of a pump embodying the inventionand Figure 2 is a cross section on the line 2-2, Figure 1.

Figure 3 is a fragmentary view illustrating a modified form of the valveshown in Figure 1.

Referring to Figures 1 and 2, there is contained in the barrel a of thepump, a reciprocatory plunger b, the discharge strokes of which areeffected by a cam c or eccentric on a rotary driving shaft d, and thesuction strokes of which are effected by a spring e. In the barrel isprovided a fuel inlet port 1 (or ports) situated adjacent to theposition occupied by the inner end of the plunger when at the end of itssuction stroke. Also this end of the plunger may be provided with aspill-passage g which, on rotation of the plunger in its barrel by anynormal governing means, controls the volume of fuel delivered in eachdischarge stroke. In the example shown, the plunger is rotatable by aslidable control bar h in engagement with a toothed sleeve 2' whichsurrounds the barrel and is connected to the plunger by a cross piece7'.

Coaxially wtih the discharge end of the pump barrel is arranged a part70 having therein a port m with which co-operates the control valve.This latter comprises a cylindrical spring-loaded plug n slidable androtatable in a bore in the part 7c. At one end the valve is formed witha conical or like part adapted to seat on the adjacent end of the saidpart. Also along an appropriate part of its length it is formed with alongitudinal groove 1) which (on rotation of the valve) establishescommunication with each in turn of a plurality of delivery passages qadapted to be connected to the engine cylinders.

Rotation of the valve is effected at an appropriate rate by a spindle 1'arranged parallel with the pump plunger. At one end this spindle is 4Claims. (01. 103-2) 2 connected through a pair of pinions s with thedriving shaft and at the other end it is connected with the valve by apair'of pinions t, u, the pinion it having extending from it a shortspindle '0 formed with a tongue w which is slidable in a slot a: in theadjacent end of the valve, the latter being loaded by a spring y.

The arrangement is such that during the suction stroke, the valve n isheld on the discharge port m by its spring 1/. During the deliverystroke the valve is moved off its seating against the action of thespring by the pressure of the fuel, and the fuel is delivered throughthe particular passage q then in communication with the groove 10 in thevalve. Preferably the portion of the valve immediately adjacent to thepart 0 which co-operates with the port m occupies the adjacent portionof the bore in which the valve is located. Also in the bore above thispart is formed an annular groove 2 with which communicates one end ofthe groove 10. The annular groove 2 is isolated from the port m by thesaid portion of the valve when the latter closes, and so eifects aslight suction in the then open delivery passage q which preventsdribbling at the discharge nozzles in the engine cylinders.

In Figures 3 there is shown an alternative form Of the valve 12. Thiscomprises a cylindrical plug as above described, but differs in thatinstead of the conical part 0 adapted to co-operate with a dischargeport m, it is provided with a short projection 0 which can rest on aplain portion of the end of the bore in the part 10, and around the saidportion are formed a plurality of discharge ports m By the use of asingle valve member as above described, which serves both for isolatingthe plunger barrel from the delivery passages during the suction strokesand for establishing communication with the appropriate deliverypassages during the discharge strokes, a pump of the kind specified canbe provided in a very simple form.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

l. A liquid fuel injection pump for a multicylinder engine. comprising,in combination, a single plunger reciprocable in a containing barrel,means for reciprocating the plunger, means associated with the plungerfor controlling the volume of fuel delivered at each discharge stroke, asingle spring-loaded and longitudinally reciprocable discharge valvecontrolling an outlet from the pump barrel to a plurality of deliverypassages, means for rotating said discharge valve about its longitudinalaxis, and means associated with said discharge valve for distributingfuel in turn to said delivery passages as determined by the rotation ofthe valve.

2. A pump according to claim 1, in which the discharge'valve comprises acylindrical plug formed at one end to control by its longitudinalreciprocation the outlet from the pump barrel, said plug having alongitudinal groove adapted to establish communication between the saidoutlet and each in turn of the delivery passages.

3. A pump according to claim 1, in which the discharge valve comprises acylindrical plug occupying a cylindrical bore, the valve being formed atone end to control by its longitudinal reciprocation the outlet from thepump barrel, the said cylindrical bore having therein an annular groovewhich is isolated from the discharge end of the pump barrel by the valvewhen the said. valve is in its closed position, the said plug having alongitudinal groove which is in communication at one end with theaforesaid annular groove and which is adapted to establishcommunication,

through the annular groove, between the said outlet and each in turn ofthe delivery passages.

4. A pump according to claim 1, comprising a rotatable spindle fordriving the discharge valve, a gear wheel on said spindle, a second gearwheel meshing with the first gear wheel and having its axis aligned withthe longitudinal axis of the discharge valve, a driving coupling betweenthe said second gear wheel and the said valve adapted to permit relativeaxial movement of the valve, and

a valve-loading spring associated with the coupling.

ALEXANDER MURASZEW.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,145,379 Vogelei et al. Jan. 31, 1939 2,174,526 Parker Oct.3, 1939 2,351,908 Beeh June 20, 1944 2,519,733 Beard Aug. 22, 19502,544,561 Meyer Mar. 6, 1951

